1. Field of the Invention
The present general inventive concept relates to an image forming apparatus and a PDP (portable document format) document direct printing method thereof, and more particularly, to an image forming apparatus to form an image without a printer driver of a host apparatus, and a PDF direct printing method thereof.
2. Description of the Related Art
An image forming apparatus forms an image on a record medium based on print data. Among image forming methods of the image forming apparatus, direct printing is widely used since the direct printing transmits unprocessed print data directly to the image forming apparatus, does not require a driver and has a speedy transmission rate.
The image forming apparatus directly prints TIFF and JPG formats having images and PDF formats having documents. As illustrated in FIG. 1A, a PDF document 101 includes a header 110, a body 120, a cross reference table 130 and a trailer 140.
The header 110 of the PDF document 101 stores a version of the PDF document 101 while the body 120 includes at least one object 121 presenting document content. The cross reference table 130 stores an offset of each object 121 in the document, and the trailer 140 transmits information about the cross reference table 130 to an application.
FIG. 1B illustrates a conventional direct printing process. If a PDF document 102 is received, the image forming apparatus stores the PDF document 102 in a storage unit 150, as determined data 160, if a determination is made that the received document is direct-printable. If the image forming apparatus does not include an auxiliary storage unit such as a hard disk, a main memory stores the document 102. A parser parses the stored document as parse data 170 and a renderer converts the parsed document into rendered data 180 as an image and prints the document corresponding to print data 190.
As each of the objects in the PDF document 102 is stored in a predetermined order, the conventional image forming apparatus should have a memory having a larger capacity than the size of the PDF document 102 to parse and print the PDF document 102. Thus, if the image forming apparatus does not include the auxiliary storage unit or an available capacity of the main memory is smaller than the size of the PDF document, the PDF document 102 may not be printed. Then, a user should find a host apparatus having an application or print the PDF document from another image forming apparatus.